Hydraulic controuring attachment for machine tools



June 7, 193.8.

L. w. WRIGHT 2,120,196 HYDRAULIC CONTOURING ATTACHMENT 'OR MACHINE TOOLS i Fi-led May 14, 1957 6 Sheets-Sheet 1 lNvENToR. LC/6H A/ MP/a/fr i BY June 7,1938. L. w. wRlGHT A2,120,196

HYDRAULIC CONTOURING ATTACHMENT FOR MACHINE T OOLS Filed May 1'4, 1957 'e sheets-sheet 2 ATTORNEY.

June 7, 193s. L, w wmGHT 2,120,196

HYDRAULIC CONTOURING ATTACHMENT FOR MACHINE TOOLS Filed May 14, 1937 6 Sheets-Sheet 3 June 7, 1938. i 1 l w WRIGHT l 2,120,196

HYDRAULIC CONTOURING ATTACHMENT FOR MACHINE TOOLS Filed May 14, 1937 6 Sheets-Sheet 4 ATTORNEY.

June 7, 1938. w, WRIGHT A 2,120,196

HYDRAULIC CONTOURING ATTACHMENT FOR MACHINE TOOLS Filed llay 14, 1937 6 Sheets-Sheet 5 ATTORNEY.

June 7,1938. 1 w. WRIGHT' 2,120,196

HYDRAULIC CNTOURING' ATTACHMENT FOR MACHINE TOOLS Filed May 14, 1937 6 sheets-sheet s INVENT OR.

ATTORNEY.

y Patented -June. 7, 1938 PATENT ori-ica g HYDRAULIC coN'roUniNG A'r'rAcnMniwrl Fon4 MACHINE Iroots f Leigh w. wright, Norwood, ohio, miglior fn The Cincinnati Milling` Machine Company. Qincinnati, Ohio, a corporation of Ohio,

Application May 14, 1937, Serial No. 142,661

V32 Claims.

This invention relates to machine tools and more particularly to improved means for rendering a standard type ofA machine tool utilizable for automatically performing contouring operations of either two or three dimensional proportions.

The conventional form of machine tool is/ usually only capable of performing a rectilinear feeding movement between the tool and work, whereby an element of the machined surface, taken in the direction of feed becomes a straight ied from a pattern.

operations.

One of the objects of this invention is to provide auxiliary control means'in the nature of an attachment whereby deviation from this straight line movement may, be effected automatically so that surfaces of undulating contours may becop- Another object of this invention is to increase the usefulness of a conventional machine tool by providing a comparatively inexpensive control mechanism which may be easily and quickly attached to the machine for rendering the same capable of performing profiling and die-sinking A further object of this invention isto which is adapted to perform a distinct function and which are readily connectible to the proper operating lead screws of the machine in accordance4 with the functions assigned to the motors; and a tracer lcontrolled circuit for automatically controlling the operation of said motors.

An additional object of this invention is to provide an improved portable hydraulic unit for transforming a plain machine tool into an automatic pattern controlled machine tool.A

Other objects and advantages of the present invention should -be readily apparent by reference to the following specification considered in conjunction with the accompanying drawings illustrative of one embodiment thereof, but it will be understood that any modifications may be made in the specific structural details within the scope of the appended claims without departing from or exceeding the spirit of the invention.

Referring to the drawings in which likereference numerals indicate like or similar parts:

Figure 1 is an elevation of a machine tool showing the mechanism of this invention applied thereto for control thereof. i

Figure 2 is a section through one of. the hydraulic motors showing the method of detachable connection to a machine tool leadscrew.,

K provide a portable unit having three motors, each of od of supporting the tracer unit on its supporting bracket for adjustment in two different planes.

Figure 4 is a detail section through the indexl ing motor showing the method of detachably connecting the same to a machine tool lead screw.

Figure 5 is a detail section on line 5-5-of Figure 4.

Figure 6 is a section on the line 6--6 of Figure 1.

Figure l is a detail section on the ,line 1-1 of Figure 6. Figure 8 is a detail view showing the manner of incorporating a Areduction drive in one of the hydraulic motors. v Figures 9, 10 and 11 are views showing different ways of utilizing thelinvention in connection with a milling machine.

Figure 12 is a plan view showing the manner of supporting the tracer ona conventional hcrizontal spindle milling machine.

Figure 13 is a plan view showing this invention applied to the control of a lathe.-

Figure 14 is a view in elevation showing this invention applied toa vertical spindle millingA e machine.

Figure 15 is a diagrammatic View of the hydraulic control circuit of this invention.

Figure 16 is a detail view of the controls on the tracer unit. This invention has been exemplified in connection with a milling machine because such machines have means for supporting a work piece for threel directional movement with respect to a cutting tool, although it will be understood that the invention is applicable to other types of machines having two directional movement. A conventional milling machine, such as shown in Figure l, has a. work table III which is movable along a first path, a saddle il which is movable along a second path at right angles to the first named path, and a knee I2. which is movable at right angles to the plane determined by the first two named paths. These three slides are. moved by conventional mechanical means, such as lead screws 1I, Il and I5 respectively. These lead screws are provided with'manually operable control levers which are usually removable. By

means of this invention, hydraulic motors may be substituted for these manually operable'levers and, with the assistance of 'a tracer control unit which may be detachably mou'nted in cooperative relation to the work table and tool spindle, various types of contouring operations may-be performed by the machine,

Briefiy. this invention consists of a portable unit, indicated generally by the rei'erence'numeral I6 in Figure 1, containing the necessary elements for puttingvoil .or other suitable operating fluid under pressure. The unit carries a secondary valve `i1 which controls the distribution of this, pressure fluid among hydraulic motors I8,

i! and 20. These motors are mounted, when not in use, on placement pads formed on the side of the unit, and when it is desired to utilize the same, they are removed and detachably connected to the proper lead screws ofthe machine. A tracer unit 2| is also provided with the unit for controlling the position of the secondary valve which determines distribution of fluid to the motors in sucha manner that a cutting path will be produced 'having an outline corresponding to the outline of a pattern carried by the table.

Attention is invited to the fact that the motors as well as the tracer unit are hydraulically connected to the secondary valve at all times, so that it is not necessary for the operator to Vmaire any pipe connections in order to utilize'this invention. An undulating cutting path which is necessary for successful performance of profiling and diesinking operations may be said to be the resultant of motions along two rectangular paths arranged at right angles to one another. One of these' paths will be known herein as the feedKpath becauseit is to indicate the general direction of `the feeding movement between the cutter and work, and the other will be known herein as the proling path because it is along this path that deviations are caused to occur and which combine to form the resultant undulating path.

In die-sinking operations, it is the usualpractice, after one cutting stroke has been executed, to eilect an indexing movement at right angles to the plane of the cutting path, and 'it is desirable thatthis function be performed automatically at the time of reversal in order that theehtire opf eration may be carried out without interruption.`

It is obvious from the foregoingl that if individual motors having specific functions are utiliaed, that each must be connected in a .definite manner to the hydraulic control circuit. In order t'o obviate the necessity of an operator making any 'pipe connections, with the greatpossibility Yof error, the function of each hydraulic motor is indicated thereon, and each motor is permanently connected to the hydraulic'control circuit in the proper manner for carrying out the function assigned thereto. For instance, the motor I8 is indicated in Figure l as the feedmotor`, the motor I3 as -the profiling motor, and themotor 20 as -the index motor. These vmotors are, how:

ever, interchangeably connectible to any one of the three lead screws of the machine sothat the operator merely has to determine which lead screw is to perform the feeding'function and attach the feed motor thereto. He then determines which lead screw is to perform the profiling function and -attaches the prolin'g motor thereto. operation, he then attaches the index motor to the remaining lead screw.

The tracer head has its control valve properly connected by exible leads for controlling the position of the secondary valve, and it is only necessary for the operator to attach thetracer head to the structure of the machine in such relation to the cutter spindle and work table thereof .that the tracer may follow the pattern.

If the operation is tobe a die-sinking the rotary type. One form of such motor is shown in Figure 2 of the drawings, and comprises mainly an operating shaft 22 upon which is integrally formed an eccentric cam 23 which is acted upon by 'a plurality of radially arranged pistons 24 having anti-friction rollers ,25 mounted in the end thereof for engagement with the periphery of the cam. Each cylinder 23 is connectedl by an linternal passage 21 formed in'the motor housing 28 to a port 29 adjacent the periphery of a distributar valve 30 rotatable with the shaft 22. Adjacent opposite ends of the distributor valve sure and exhaust.

The motor shaft 22 has an axial bore 34 formed in one end thereof for receiving the projecting end of a machine lead screw. Adjacent the periphery of this bore are clutch teeth 36, which are adapted to interengage the clutch teeth 31 formed von the sleeve 33', which is integral with the lead screw and constitutes part of the ma,-4

chine. A suitable mounting bracket A39 may be -secured to the end of the lead screw housing 40,

as by bolts 4|, and the motor attached to this bracketiby' means of screws 42 passing through the motor frame.

Both the' feed motor andthe prole" motor lhave a reversing valve slidably mounted in the /alo 5 motor housing, and the grooves 3| and 32 are connected respectively to ports 42 and 43 of this valve. As shown in Figure l5, the feed motor control valve housing 44 has a pressure port 45 which isconnected by channel 46 to port 41 of a start and stop control valve 43 which is mounted on the control unit. It also has a pair of ports and 50 which are interconnected to a return channel 5l terminating in port 52 of valve 4I. The,

valve plunger 53, which is shiftable by the man-- ually operable handle 5 4, has a pair of grooves l5 and 58, whereby `pressure port may be selectively connected to either port 42 or 4 3 for reversible operation of the feed motor, whilethe remaining port is connected to one of the exhaust ports 43, 50.

The control valve housing 56 for the profile" motor has a pairof ports 51 and 53, which are connected by flexible channels 59 and 30, respectively, to ports 6I and 32 of the start and stop control valve 48. The valve 56 has a plunger 33 which is shiftable by a manually operable handle 64. It will be noted that in theistop position a pair of spools 65 and 33 formed on the valve plunger arein a position toblock ports 51. and 5I. but when the plunger is shifted to the left as viewed in Figure 15, a pair of annular grooves 61 and ,38 serve to interconnect port 51 with 43,

and port 53 with 42; 'and when shifted 'to' the andV port giijnto port 42. y

The indexing motor 20 is difl'erent in con'- structionyfrorn the other two motors and the details thereof are more specifically shown in Figures 4 and 5. lI 'his motor comprises a housing 63 in which isv formed a cylinder 10 having a contained piston 1i. As shown in 'Figure 5, the piston 1I has two arcuate notches 12 and ,13 axially spaced on the periphery thereof, whereby a plungery 14 supright, the 'grooves-interconnect port 53 to port 43 ported for reciprocation in a radial direction with aspect to the axis of the piston 1I will execute` one reciprocation for each stroke of the piston.

. T'he plunger 14 has rollers 15 rotatably mounted at each end thereof, one of which engages the notchesA in the.piston, and the other of which engages a shoulder 16 which is cut in the periphery of the hub 11 of indexinglever 18. A spring 19 has oneend attached to a pin 80 carriedby the hub 11 and the other end to a pin 8| carried by the casing to urge the lever 18 normally in a clockwise direction as viewed in Figure 5. The free end of the lever 18 carries a pawl 82 which engages the 4notched periphery of the index wheel 83.

When pressure is admitted to either end of cylinder 10, the piston 1| immediately moves to the other end, thereby causing a reciprocation of plunger 14 which, during the outward movement.-

l will rotate the index lever in a counterclockwise direction, causing movement of wheel 83, after which the spring 19 will return the parts to the position shown?.

The housing 6951s secured to the machine frame 84 as by bolts 85. This housing carries a gear 86 which is held in position bymeans of pins 81 riding in an annular groove 88 formed on the hub of the gear. The gear 86 intermeshes with a gear 89 which is keyed to the reduced end 90 of a shaft 9|. This shaft is held in a bearing 92 forming part of a member 93 which is secured to the frame 69 by bolts 94. The member 9| has gear teeth 95 cut in the periphery of an annular rib formed thereon for interengagement with a pinion 96 formed on the end of shaft 91 which shaft'has a gear 98 integral with its other end and intermeshing with a pinion 99 supported for free rotation relative to the member 9|. .The pinion 99 is keyed for rotation'with .a manually operable handle which carries a pin |0| adapted to. engage any one of a series of holes |02 formed in the index wheel 83.

The gear 86 has clutch teeth |03 formed on one face thereof for interengagement upon assembly with similar formed clutch teeth formed on the member |04 which is a part of the machine and |02 by pulling on the handle |06 and then rotatj ing the lever |00 the prescribed amount.

For automatic operation, the opposite ends of cylinder are connected by channels |01 and.v

|08 to ports 42 and 43 ofthe reversing valve 44 of the feed motor.

Since there are times when the index motor will not be utilized or even mounted on the ma'- chine, means have been provided for cutting out the index motor regardless of whether it is mounted on the machine or on its placement pad on the unit, Aand without the necessity of the operator connecting or disconnecting any pipes. This means comprises a Valve |09, associated with the motor having a rotatable valve plunger ||0 in which two cross bores `are drilled. When the plunger is in the position shown 1n Figures 5 and 15, the lines |01 and |08 are connected to the ports 42 and 43 whereby upon each reversal o! the feed motor the piston 1| executes one stroke and thereby a predetermined amount of indexing of the machine lead screw to which it is attached. Upon rotation .of the plunger ||0 through an angle of 90, the index motor is disconnected from the feed motor supply ports and thereby rendered inoperative.` It will be obvious, however, that if the motor is attached to the machine, the indexing mechanism may still be manually actuated as for set-up purposes.

An automatic tracer lcontrolled mechanism has been provided'comprising a tracer head ||2 in which is slidably mounted a valve plunger H3. A tracer ||4 has an integral ball-shaped portion ||5 intermediate of its length by which it is supported for universal movement in the tracer head. A ball ||6 is interposed between a depression formed in the upper end of the tracer arm, and a similar depression formed in the lower end of the valve plunger, whereby upon deflection of the tracer arm from a central vertical position, the valve plunger I3 will be caused to move upward. A spring l I1 is interposed between the upper end of the valve plunger ||3 and the cap ||8 of the tracer head for exerting a continuous downward urge on the plunger ||3, which reacts through the ball ||6 and tends to centralize the tracer arm I|4 in a. vertical position.

The tracer valve serves through hydraulic am plication means to control the position of a secondary valve plunger A||9 which is slidably mounted in a housing |1. This is 'accomplished in the following manner. A pump |20, mounted on top of the unit I6 and driven by an electric motor |2|, has an intake |22 through which uid is withdrawn from alreservoir |23 contained in Y respectively to chambers |33 and 34 formed in the end of the valve housing. These chambers are connected by channels and |36 to ports |31 and |38 of the tracer controlled valve. A third port- |39, intermediate ports |31 and |38, is connected by channel to reservoir.

The valve plunger ||3 has a pair of annular grooves |4| and |42 formed therein and separated by an intermediate spool 43. This spool is movable -relative to port |39 which port is slightly wider than the width of spool |43, whereby When the spool |43 is centrally located with respect to port |39, the resistance to-ow of fluid from ports |31 and |38 to reservoir is equal, which would thereby normally cause equal pressure in channels |35 and |36. If this pressure is not equal, then the pressure in chambers |33 and |34 will not be equal and since the valve plunger ||9 is always free to move, it will shift in such direction as to cause equalization of these pressures.y

This is based on the proposition that when the values of two serially connected resistances are` spool |21 at port |25 is equal to the value of the` ports |25 and resistance to flow from port |31 to reservoir, that the pressure in channel |35 will be equal to one- 'nsA sures acting o'n the end of plunger ||9 will be equal and the same will remain stationary.

It now the tracer valve plunger ||3 moves 'downward from its central position as 'viewed in Figure 15, the resistance to iiow from |36 to reservoir will increase and the resistance to flow from |31 will decrease, thereby causing a rise in pressure in line |36 and a fall in pressure in line |35. 'I'his will cause a pressure differential on the ends of plungerl I6 causing the same to shift to the left as viewed in Figure 15 due to the higher pressure in channel |36, which will increase the re-l sistance at port |26 and decrease the resistance at port |25. The result is an increase in the pres- .sure dropat port |26 and a decrease in the pressure drop at port |25, which tends toward equalization of pressurein chambers |33 and |34, and the movement of valve plunger ||8 will continue until this equalization has been brought about.

Thus the secondary valve is caused through remote control to take up various positions in accordance with the position of the tracer oontrolled valve. The secondary valve controls ,the proportional rates of rotation of the feed and profile motors in the followingv manner. A variable delivery pump |44 mounted on the unit |6,` and driven by an electric motor |45, provides the pressure iiuid for operating these motors, and has an intake |46, through which uid is withdrawn from the reservoir |23; and afdelivery pipe |41 which terminates in pressure ports"|48 and |48 in the secondary valve. The secondary valve plunger has an annular spool |50, and annular grooves and |52 on vopposite sides thereof. This portion of the valve serves to control reversible operation of the profile motor, and to this end the valve is provided with ports |53 and |54 to which are connected channels |55 and |56 which eventually lead to the pro'le motor. Additionally, the secondary valve has a pair 4vof exhaust ports |51 and |56 which are connected to a return line |59.

When the secondary valve plunger ||8 is in a central or neutral position, the spool |50 closes the pressure port 48 and no fluid is owing at thisl time to the profile motor. This means that the tracer ||4 is sufiiciently deflected to hold the tracer controlled valve plunger ||3 in -its centralor neutral position. It will now be apparent that if the pattern causes a greater deflection of the tracer or permits a lesser deiiection of the tracer, that the secondary valve plunger will shift either to the right or to the left of -theposition in which it is shown. In this case pressure fluid will be delivered either to channel |55 or channel |56 and cause rotation of the profile motor ina clock#v wise or counterclockwise direction.

A single channel |60 supplies fluid pressure to tity of iluid delivered to channel |60 will be reduced and the remainder of the low will then be delivered to either channel |55 or |56. Thus the secondary valve divide's the vflow from pump |44 between the ffeed and .profile motors to produce an undulating cutting path.'

It is necessary, however, in order to maintain proportional division-of flow as,set up` by the j I secondary valveto provide a pair of balancing' valves. To this end the feed channel |60 is con- |66l are'each halfway open.

Since either line |55 or |56 may-be under pressure,I it is necessary to connect the feed line tov a second balancing valve so as to balancetlie iiow therein against the line |55 when the same is under pressure. To this end the port' |65 is connected by channel |61 to the end of'balancing .valve |68 and the other end of, this balancing valve is connected to line |55. This valve has a plunger |68 with tapered ends which is movable to control the flow through ports |10 and |1|. Port |10 is connected bychannel |12 to port |13, and' port |1| is connected by channel |14 to ports and |16, and port |66 is connected by channel |11 to port |18, all of these last named ports being in the start and stop valve 46. 'When the start and stop valve plunger |19 is lin the running position in which it is shown in Figure 15, port |13 is connected by annular groove |60 to port 41 which leads to the feed? motor; port |15 is connected by annular groove |6| to port and port |16,-is connected by annular groove |62 6| which leads to one side of the proflie motor; 'y

to port 62hich leadsl to the other side of the pronle motor.

The use' of balancing valves to maintain the division of ow among two or more hydraulic motors does not constitute part of the present invention, the .same having been disclosed in U. S. Patent N0. 1,999,834 issued April 30, 1935.

The valve plunger |19 is shifted by a control lever |83 which is pivotaliy supported in a bracket |64 mounted on top ofthe unit|6 and has a f connection at |65`to the plunger |18. The leveris shiftable clockwise to a stop position indicated by' the dash and dot line |66 in which position the spool |61 will close port 4 1, the spool |66`will close port 6|, and the spool '|68 will close portA |62. Thus the threemotor ports are disconthe feed motor, and thischannel is connectewected from the secondary valve.

to port |6| of the secondary valve, whereby a groove |62 formed in the valve plunger will connect port |46 to port |6| when the plunger ||8 is in its. neutral position. It will be noted that the ,annular groove |62 is of such length that when the plunger ||9 is in its central position, ports |6| and |46 will each be half closed. .This means 'v that when the plunger ||9 is shifted eitherto the In order to prevent high pressures building up in the pump delivery lines, means have been provided for connecting these pumps to reservoir when the valve is in thestop position. To this .end the delivery channel |24 of pump |20 has a branchv connection to -port |62. The delivery channel |41 of pump |44 has a branch connection to port |63 which is connected by annular groove |94 to reservoir port |85.

In the operation of the machine, the stop valve plunger |13is set in a stop position, and the `pumps are started by energizing the electric motors |2| and |45. At this time the tracer is not in contact with the pattern and is therefore undei'iected, which means that thespool |43 'on the tracer valve is on` the lower side of port |34 as vgiriamo viewed in Figure 15, whichwould thereby raise the pressure in line |36 and lower the pressure in line |35, thereby shifting the secondary valve chine lead screw to which it is attached in one direction thereby causing one direction of movement of the pattern support. It may be desirable, however, for set-up purposes to move this support in an opposite direction or to movethe support which is actuated by the lead screw attached to the feed motor. To this end, means have been provided for controlling the position of the secondary valve independently of the tracer so that the secondary valve may be selectively positioned -to supply fluid pressure to the motors severally. This means comprises a rotatable selector valve |96 which is interposedin the channels |35 and |36 leading to the tracer controlled valve, whereby the channels |35 and |36 may be disconnected from the tracer valve and connected to a manually controlled valve |91 which is movable through various positions to effect different positions ofthe secondary valve. In other wordsfthe valve plunger |96 has a pair of L-shaped passages |98-and |99 which, in the position shown, serve to connect channels |35 and |36 to ports |31 and |36 respectively of the tracer controlled valve. When the plunger- |96 is rotated counter-clockwise through an angle of 90 as shown in Figure 16 the channels |35 and |36 are then connected through branch lines to ports 200 and 20| of the manual controlled valve |91. This valve has a Y-shaped passage 202 for simultaneously connecting ports 200 and 20| to an exhaust port 203 leading to reseryoir. In

order to insure` a sufficient rise in pressure in channels |35 and |36 to Jcause shifting of the secondary valve' to its vcentral position, if`it is not in that position, a suitable hydraulic resist-` ance 206, which may be in the form of a coil of small bore copper tubing, is inserted in the reservoir line 205. If the resistances at ports 200 and 20| are equal, the secondary valve plunger ||9 will shift to acentral position in order to make the hydraulic resistance created by the spools |21 and |26 equal. In this position of the secondary valve, it will be noted that the spool.|50 will disconnect the'pump |44 from theI prole motor and permit all the flow to go to the feed moervoir and close port 200 thereby, causing a rise in pressure in channel |35 which will shift the secondary valve to itsv extreme right position. This makes it possible to disconnect the pump |44 from the feedline and selectively connect it to either one of the proe" motor supply channels.

With the reversing valve .plunger 63 in a central position, it is possible to manipulate the profile motor to cause adjustment of the connected slide It is possible by means of these manipulations to establish contact between the tracer and pattern, after which the stop valve may be moved to its stop position and the reversing valves 53 and 63 properly positioned in accordance with 5 the desired direction of feed and proling. Afterv setting the selector valve |96 in a position to connect the channels |35 and |36 to the tracer, the stop valve is shifted to its running position, whereby the contouring operation will automatiJ 10 cally begin. A

It will be obvious that when the secondary valve is in a position to deliver fluid pressure to channel |55, that channel |56 will be connected to reservoir and therefore have avery low pres- 15 sure therein., This means that the balancing valve plunger |64, for instance, will shift to its extreme right hand position, practically closing port |66 which would thereby stop the return 110W. To eliminate this condition and permit no substantially free passage of fluid to reservoir through either channel |55 or |56, as the case may be, check valves 206 are connected in-parallel with one end of the balancing valves so that the check valves will open during the return flow, but g5 Awill close under a pressure flow in the opposite direction. 'I'his makes it possible for either balancing valve to be effective Afor balancing purposes without interfering with the return flow through the other channel.

In profiling operations such as following around the periphery of a rectangular shaped pattern, it

ymay be desirable to change the general feeding direction, or in other words reverse the functions of the feed and prole motors. 'I'his may be 35 instantly accomplished by pulling thestop pin a 209 which will permit the stop lever |03l to be thrownpast its stop position to a third position, which will then connect the feed port |6| of the secondary valve to the profile motor and con- 40 nect the'ports |53 and |56 to the feed motor.

In other words, when the lstop plunger |19 is shifted to its extreme right hand position, port |16, which is the terminus/of line |55, is con` nected by annular groove 2|0 to port 41 of the 45 feed motor and port |18, which is the terminus of line |56, is connected by annular groove .|62 to port 52 of the feed motor, whereby the latter is now reversibly controlled by the reversing por'- tlon of the secondary valve. The feed line' 655, 50 which terminates at port |13, is connected by annular groove to port 6| of the prole" motor which will thereby cause rotation of the profile motor in one direction determined by the position of the reversing valve 62. The chan- 55 nel |60 is lnow a return channel and port 62 is connected by annular groove 2|| to exhaust port 2|2.

In vorder to obtain the greatest benets from this invention 'and increase its universality of ap- 00 plication to varying, conditions, the tracer unit 2| is mounted 'oxfan angular bracket 2|3, as more particularly shown in Figure 3, and one leg of vthis bracket is provided with a circular T-slot 2|4 in which are mounted T -bolts 2|5 which are adapted to pass throughfholes in the mounting pad 2|6 integral with the tracer unit, whereby the tracer unit may be clamped in various angular positions lying in a plane-parallel to this leg of the bracket. In-additionfthe bracket itself 7d is movable about'aI center indicatedv bythe dash f and vdot line 2|1 which is the center ofva second cirulariT-sl'ot 2|8 formed on one face of aisupporting lslide 2|9.` Clamping bolts-220 mounted in this T-slot and passing through the other leg" 15 of the bracket 2|'3 serve to clamp this bracket in various angular positions about the center 2 and 222 and threaded through a. nut carried by the slide 2|9 whereby upon rotation of the screw the slide and thereby the tracer head may be4 variably positioned therealong in various spaced relation with respect to the cutter.

In Figure 12, this invention is shown applied to a conventional horizontal -spindle knee and column type milling machine. In this figure the reference numeral 224 indicates the spindle of the machine to which a profiling or engraving tool 225 is attached for rotation thereby. In this case the bracket 222 which supports the tracer unit is' attached to the side of the machine and by rotationof the lead screw 223 by means of the handle 226, the tracer |I4 may be spaced with respect to the cutter 225 in the same relation that the pattern 221 is spaced from the work piece 223. It will be apparent that by attachingl the feed motor i9 to the lead screw of the table I9, and the profiling motor I9 ,to the lead screw of the -saddle that anundulating profile, such as 223,

on the pattern, may be reproduced on the' work automatically.

If the faceof the pattern is sufficiently wide to require more lthan one cut it is apparent at the end of one stroke of the table that the operator can throw the reversing valve 54 for the "feed" motor so that a cutting stroke in the return direction `may be eilected. ABy attaching the index motor to the elevating screw for the knee, the table I3 may be indexed vertically and automaticallyeach time the reversing valve 52 is shifted from one extreme position to the other.

It is desirable, however, in performing operations of this nature that the operator may readily view the 'work during the cutting operation, which is not so easy with the set-up shown` in Figure l2, and therefore it would be more desirable from a practical standpoint to use some form of attachment such as that shown in .Figures 6 and 7 whereby the cutter spindle 'may be arranged in a more desirable relation with respect to the work and the operator. 'Ihis attachment comprises `a housing 229 havingguideways 230 by which it may be attached to an overarm 23| carried by the machine. A shaft 232 is antifriction- .housing 229 to be adjusted along the. overarm' without breaking the driving connection with the spindle.

The shaft `232 has a gear 235 secured to the end thereof in operative driving relation to a pinion 233 which is also antifrictionally supported in the housing. Integral with the pinion 233 is a 4gear 231 meshing with gear 233. This gear iskeyed to the end of shaft 239 which shaft. as shown in Figure '1, terminatesin a. bevel gear 243. This bevel gear meshes with a similar bevel gear 24|.

keyed to the end of a cross shaft 242. This shaft in turn is connected by bevel gearing 243 for driving a. sleeve 244 in which is splined the cutter spindle 245. 'The sleeve 244 is antifrctionally journaled in a housing 246 which is angularly z adjustable about the center of shaft 242 and with respect to its supporting bracket 241. A circular 'T-slot 250 is formed in the housing 229 and .by

means of T-bolts 25| passing through the bracket 241, the cutter spindle may be adjusted angularly -in a second plane at right angles to its rst plane of adjustment.

'I'he end of the cutter spindle 245 has a conventional tapered socket in which various cutting tools 25| may be secured. It will be noted that the cutter spindle is angularly adjustable in'two planes in a similar manner to the adjustment of the tracer.

The advantage of using a universal cutter spindle support, such as shown in Figures 6 and 1, is

brought out in Figures 9, 10 and llof the drawings. In Figure 9 the cutter spindle 25|` and tracer |4 are adjusted to a horizontal position whereby die-sinking operations maybe performed with the. profiling motor i9 attached to the table lead screw for controlling tn'e profiling movement and the feeding movement may be effected either in a vertical direction by attaching the "feed motor I8 to lthe knee elevating screw or in a horizontal direction by attaching the feed" motor to the saddle lead screw. In either case the operator may-easilyI watch the cutting operation and by attaching the index motor to the proper lead screw, he only has to operate the vreversing valve 53 at the end of each cutting.

stroke, the reversing valve being associated with the feed motor and being easily accessible from a position in which he can clearly watch the cutting operation.

In Figure 10,'the parts areshown in the opposite position.- In Figure 11 there is shown a set-up whereby male parts may be cut from female parts,`or vice versa, and in this case,

the cutter 25| and the tracer II4 are supported in such a manner that they point in opposite directions. Again the profiling motor I9 may be attached to the table-lead screw and the feedf motor attached to. the knee elevating screw and the index motor 20 attached to the saddle lead screw.

In Figure 14, the invention is shown adapted to a verticalA spindle milling machine for performing`a, die-sinking operation in which case the feed motor I8 may be attached to the table.lead screw and the profiling motor |9attached to the knee elevating screw with the indexing function being performed by the index" motor 2li attached to the saddle lead screw.

In Figure 13, the application of the invention to other types .of machine tools besides milling machines is illustrated-in this case the machine tool being a lathe; lathe may be provided with a bracket 252 Afor supporting a pattern 253 in operative relation to the tracer unit 2| which may' be mounted on l thecross slide 254 of the lathe. As is usual in such machines, the cross slide 254 has a manually operable screw to the .end of which the proling motor I9 may be attached. The crossl For reproducing purposes, the

` fluid under pressure to said motors including aslide 26| is usually mountdon a notch 255 traversed by a lead screw 256 and in this case, the "feed motor I8 may be attached to the end-of this screw whereby a lathe tool 251 may be traversed along a rotating work piece 258 and moved radially with respect thereto under automatic control for reproducing an undulating contour on the work piece. n

It may be found desirable on heavy work to increase the torque on the output shaft of the hydraulic motors and to this end, as shown in Figure 8, the output shaft of the hydraulic motor may be connected by a reduction gearing 259 t the nal output clutch member 36.

There has thus been provided novel and improved means for converting a conventional machine tool into a contouring machine whereby irregular contours may be automatically reproduced thereby increasing the usefulness ofsuch machines.

I claim:

1. In a machine tool having-a tool support and a work support and rotors for effecting relative movement between the supports in two directions at right angles to each other, the combination of means whereby a pattern mounted on one of said supports may be automatically reproduced by the machine, including a pair of fluid operable mo tors detachably connectible to said rotors, a portable unit external of the machine for supplying control valve; a tracer unit attachable to the other of said supports in cooperative relation with the pattern, and remote control connections coupling the tracer for control of the valve in said portable unit. l

2. In a machine tool having a tool support and a work support, a metal working tool mounted on said tool support, and rotors for effecting relative movement between said supports in right angular directions, the combination of means for automatically reproducing a pattern with said machine, including a` pair of fluid operable motors connectible for power actuation of said rotors, a portable unit for supplying fluid pressure to said motors, including a flow dividing valve; a tracer mountable-upon one of said supports in cooperative relation to the pattern carried by the other of said supports for deflection thereby, pressural control channels coupling the tracer for shifting said valve in accordance with the amount of tracer deflection, means coupling one of said motors to the valve for several operations when the tracer is in a predetermined deflected position, and means coupling the other motor to said valve for joint operation with the other motor when the tracer departs fromsaid predetermined deflected position. y

3. In a machine tool having a work support and a cutter support, a cutter carried by said support, and individual rotors arranged in planes normal to one another for effecting relative movement between the supports in right angular paths whereby a rectilinear cutting path may be effected in either direction, the combination of means for rendering said cutting path non-rectilinear, including a first fluid operable motor connectible to one of said rotors for feeding along one path, a second fluid operable 'motor connectible/,to the other rotor for 'causing departures from said feeding path and thereby creating a non-rectilinear path, a control valve external of the machine, a source of pressure connected thereto, said valve having a first position for connecting said source of pressure to the first named motor forseveral operations thereof, and other positions for connecting said source of pressure to both of said motors for'joint operation, a tracer unit attachable to one of said supports and having a deflectable tracer, and means operatively connecting said tracer for governing the position of said valve in accordance with the deflection thereof by a pattern. 4. In a machine tool having a work support and a rotatable tool spindle, the combination with a pair of rotors for effecting relative movement between the support and spindle in a first direction transversely to the axis of said tool spindle, and in a second direction parallel to the axis of said tool spindle, of means for rendering the machine adaptable for contouring operations, including a portable unit positionable in proximate relation to the machine and having means for providing fluid under pressure, a pair of hydraulic motors permanently connected hydraulically to said unit, means for operatively connecting said motors to said rotors, a tracer unit attachable to said machine in cooperative relation to a pattern carried by the work support. said tracer unit having a tracer arm deilectable by the pattern, andl means in the portable unit remotely controlled by said tracer in accordance with the deflection thereof for governing the distribution of fluid from said unit to said motors.

5. In a machine tool having a tool support and a work support, and rotors for effecting relative movement between the supports in right angular directions, the combination of means for converting the machine into a modeling machine, including a portable unit positionable in proximate relation to the machine, said unit having means for developing fluid under pressure, a pair of fluid operable motors carried by the unit for detachable connection to said rotors, a control valve in said unit, means permanently hydraulically connecting said motors to said control valve, a tracer detachably connectible to the machine incooperative relation to the pattern, and pressural control connections from the tracer to the valve whereby the tracer may remotely control the distribution of fluid pressure from said unit directly to said motors.

6. In a machine tool having a pair of rotors for effecting relative movement between the work support and tool support of the machine along rectilinear paths, the combination of means 4for rendering said paths non-rectilinear in accordance with the outline of 'a pattern, including a portable unit having fluid operable motors detachably connectible to said rotors, means in 'the unit forl supplying fluid under pressure, a valve in the unit for selectively connecting said fluid supply vfor joint or several operations of said motors, and means forming a part of said unit and \cleiachably connectible to said machine and responsive to departures in said patterny from a rectilinear line for remotely controlling the position of said valve and-thereby'the proportion of the rates of operation of said motors.

7. In a machine tool having angularly arranged lead screws for effecting relative movement between a tool support and a work support and normally operable to establish a'rectllinear cutting path, the combination of means for. causing hydraulic motors detachably connectible to said screws, a tracer for following the outline of said pattern, means external of the machine for supl.eso

plying uid under pressure, and including a control valve for governing the distribution of said fluid to said motors, and hydraulic motiontransmitting connections from the tracer to said valve `for governing the .position of the latter in accordance with movements of the tracer as efiected by the pattern,

8. In a machine tool having angularly arranged rotatable lead screws for effecting relative movement between a work support and a tool support in two rectilinear dire'ctions, said work support adapted to have a pattern positioned thereon -with the general direction vof its .prole parallel to one of said lead screws, means for rendering the machine tool capable of reproducing said pattern, including a portable unit having a pair oi fluid operable motors permanently connected hydraulically to said unit, means in the unit forcreating a source of fluid pressure, a control valvel having a rst position for connectingvsaid source of fluid pressure to the first of said motors and other positions for dividing the flow of pressure iluid among both of said motors, Imeans to detachably connect the firstI of said motors to the lead screw which is parallel to the general direction of'said profile to effect a substantially continuous movement between the tool support and work support, means to detachably connect the remaining motor to the remaining lead screw` for causing departures from the general direction of the feeding movement and thereby cause 4the tool toreproduce the outline of said pattern, and means permanently connecting the tracer hydraulically for remote control of the valve in said unit.

9. In an attachment for rendering rectilinearly cutting machine tools adaptable for profiling purposes, the combination of a portable unit having a pair of rotary hydraulic motors, pumping means carried by the unit' for delivering fluid under pressure, a control valve for governing the distribution of said fluid among said motors, said motors being permanently connected hydraulically to saidcontrol valve, said connections including flexible channels whereby the motors may be removed from the unit and operatively connected to the lead screws oi' said machine, a tracer unit including a tracer, means to detachably mount said tracer unit on the machine with the tracer in cooperative relation to a pattern carried thereby, and means operable by the tracer for remptely controlling thepositi'on of said control valve.`

, 10. In a portable unit forv rendering rectilinearly cutting machine tools adaptable for Vprofiling operations, the combination of a housing having a iiuid reservoir therein, pumping means carried by the housing for withdrawing iiuid from said tions -being of sufficient length to permit removalV oi said motors from said pads for detachable connection to lead screws of the machine, a tracer head carried by said u'nit and removablel therefrom for attachment to the machine tool in cooperative relation vto a pattern, and ilexible channels connecting said tracer head to said tracer controlled valve for hydraulicaly controlling the position thereof in accordance with variations Ain the pattern, to causevariation in the relative rates of Vactuation of said-motors.

1l.' In a machine tool havingatoolsupport and na work support and rotors for eiecting relative movement between the supports in two directions at right angles to each other, the combination of means whereby a .pattern mounted on one oi said supports may be automatically reproduced l54:1 the machine, including a pair of fluidl operable motors detachably connectible to said rotors, a portable unit having means therein for supplying iluid under pressure to said motors', including a control valve shiftable to vary the proportional rates oi' operation of said motors, a tracer unit detachably mounted on the other oi.' said suu-v ports in cooperative relation with the pattern, motion transmitting connections from said tracer unit for shifting said control valve and said motors for stopping relative movement between thel supports.

12. In a machine tool having a tool support and a work support and rotors for eiecting relative movement between the supports in two directions at right angles to each other, said rotors terminating in clutch portions, the combination of means whereby a pattern mounted on one of said supports may be automatically reproduced by the machine, including a pair of rotatable iluid operable motors, said motors terminating in clutch portions for detachable connectionto said rotors,

a portable unit having a fluid reservoir and a and a. work support and rotors for effecting relative movement between the supports intwo right angular directions, the combination of means whereby a pattern mounted on one of said supports maybe automatically reproduced by the machine, including a pair of iluid operable mot'ors detachably con'nectible to the respective ro-l tors, a portable unit having a uid reservoir, a

`pump Afor delivering iluid from` said reservoir under pressure to said motors, including a control valve'shiftable to determine the rate of uni-` directional actuation of one of said motors and the rate of reversible actuation of the other oi said motors, a' tracer unit adapted to be mounted on the machine with its tracer in cooperative relation with Athe pattern, motion transmitting connections coupling the tracer for variably shifting said valve, and additional valve means -associated with each motor for control thereof.

14. In a machine tool having a tool support and a work support and rotors for effecting relative movement between the supports in right angular directions, the combination of means whereby a pattern mounted. on one of said supports may be automatically reproduced in the machine, including a fluid operable feed motor, a iluid operable proilling motor, said motors terminating in clutch portions for detach-- ,able connection to said rotors, a. portable unit having means for supplying uid under pressure for actuation of said motors, including a control valve, means connecting the freed motor to said valvein a manner for determining unidirectional actuation thereoif', means connecting the proilling motor to said valve in a manner for controlling reversible actuation thereof, and a tracer unit mounted on the machine and havingvremote control connections for determining the position of said valve. i

. 1'5. In a machine tool having a tool support and a work support and rotors for eilecting relative movement between the supports in two angularly related directions, the combination of means whereby a pattern mounted on one of said supports may be automatically reproduced in the machine, including a ieed" motor and a proling motor, said motors having means j operative relation withthe pattern and having. remote control connections for governing the position vof said control valve, and means associated with the feed motor for reversing its direction of actuation.

16. In a machine tool having a tool support and a work support, a metal working tool mounted in said tool.support, and rotors for effecting relative movement between said supports in right angular directions, the combination of means for reproducing a pattern in said machine, including a. pair of iluid operable motors detachably connectible, for poweractuation of said rotors, a portable unit for supplying fluid under pressure to said motors, including a ilow dividing valve,'a tracer adapted to be detachably mounted upon one of said supports in cooperative relation with a pattern carried by the other of said supports, pressural control' channels coupling the tracer for shifting of said. valve in accordance with the amount of tracer deection, means coupling the motors to said valve for joint or several uni-directional actuation of one of said motorsand joint reversible actuation of the other of said motors. Y

17. In a machine tool `having a tool support and a work support, and rotors for effecting a relative movement between the supports-at right angles to each other, the combination of means whereby a pattern mounted on one of said supports with the general plane of its proille lying parallel to one of said rotors may be automatically reproduced, including a ffeed motor and a profile motor, said motors terminating in clutch portions whereby the feed motor may be detachably connected to said one rotor and the other to the remaining rotor, a remote con.

trol valve external of the machine for governing uni-directional actuation of said feed motor and reversible actuation of said fproilling motor, and a tracer adapted to be mounted lon the machine in cooperative relation to said pattern, and remote control motion transmitting connections coupling the tracer for governing actuation of said control valve.

18. A portable attachment for convertingmachine tools having a plurality of lead screws for effecting three-directional movements between a work support and a cutter support for utilization in die-sinking operations, comprising a conhaving `exible channel connections to said 'con' trol valveior remotely controlling the position thereof, and a iluid operable index motor havv ing means for detachable connection to the remalning lead screw for shifting the cutting vplane relative tothe work.

19. An attachment for converting a kneeand column type milling machine for die-sinking purposes, comprising a portable unit having a v reservoir of iluid medium therein, a tracer controlled ow dividing valve. a pump for delivering said uid medium from the reservoir to said valve under pressure, aplurality of hydraulic motors having permanentexible uid connections to said valve,means on said motors 'for detachable operative connection selectively to the leadl screws of the saddle, table -and knee of.said machine, and a tracer having flexible uid connections for under pressure, a control valve for distributingsaid medium to the motors, permanent flexible channel connections connecting the motors to said control valve whereby universal movement in one plane between the cutting tool of the machine and the work table may be eii'ected, said unit having a tracer head and a valve therein for hydraulically controlling the position of said control valve, flexible channels connecting the tracer head to said unit whereby the tracer head may be remotely positioned with respect to said unit on a iixed part of the machine in parallel relation to the axis of the cutter, a fluid operable index motor having means for detachablecon-` nection to the operating screw for the knee, I

flexible channels connecting said index motor to the channels of the motor that effects the feed.- ing movement, whereby each time the feeding motor is reversed a relative indexing movement between the tool and work will be effected.

21. Means for rendering a knee and column type milling machine utilizable for die-sinking purposes, comprising a portable unit having a reservoir of fluid medium therein, a pair of fluid rotatable motors, one of said motors having means for detachable connection to the table of saidy machine, the other of said motors having means for detachable connection selectively to the operating screw of either the saddle or the knee of` said machine, an index motor selectively connectible to the remaining operating screw, a

control valve for determining proportional rates of operation of said rst two motors, a pump for delivering iiuid from said reservoir to said valve under pressure, exible channel connections coupling said motors to the control valves, a tracer adapted tobe detachably mounted on the machine, including' remote control connections forA governing the position of said control valve,v

means for reversing one of said first two named motors to change the direction of feed, and means to simultaneously cause actuation of said index motor each time the other motor is reversed.

22. Means for rendering a knee and column type milling machineutilizable for die-sinking purposes, comprising a. portable unit having a reservoir of fluid medium therein, 4a. tracer controlled flow dividing valve, a tracer head detachably mountable `on the machine, including a tracer, means responsive to deflection thereof for governing the position of said iiow dividing valve, a pair of rotatable hydraulic motors connected by flexible channels to said flow dividing valve, said motors having terminal clutch portions,

whereby one of them may be detachably connected to the saddle lead screw of the machine,

and the other connected selectively to the table ably connectible to one of said lead screws forA ,effecting relative movement between said supports in one direction, a second hydraulic rotatable motor detachably connectible to a second of said lead screws for effecting relative move ment between the supports in a second direction, a fluid operable index motor detachably connectible to the remaining lead screw for effecting relative movement between the supports in a third direction, a portable unit, including means for determining the distribution of fluid pressure among said first two motors, a tracer contactable with a pattern carried by one of said supports, means associated with one of said first named motors for reversing the direction of rotation thereof, said means also being operable to cause actuation of said index motor each time the direction of rotation lof the controlling motor is changed. I

24. In a machine tool having a reciprocable work support and a cutter spindle supported for rotation about an axis parallel to the direction of movement of the work support, the combination with a ilrst lead screw for reciprocating said/ 4work support, and a second lead screw for effecting lateral adjustment of the work support, of a portable unit, including a pair of rotatable hydraulic motors having terminal driving portions for detachable engagement with portions on the ends of said lead screws, a tracer head having a tracer supported therein for universal movement, means to support the tracer head in the machine .with the axis of the tracer in coincidence with the axis of the'tool spindle, pressure fluid supply means in said unit, a valve for controlling the distribution of pressure iiuid to said motors,

and motion transmitting connections coupling the tracer for control of the position of said valve. 25. In a machine tool having a reciprocable mote control connections coupling the tracer for governing the position of said control valve.

26. Ina machine tool having a tool support and a work support, and rotors foreffecting relative movement between the supports in two angularly related directions, the combination of means whereby a pattern mounted on one of said supports may be automatically reproduced in the machine, including a feed motor and a profiling motor, said motors having means for detachable connection to the respective rotors for actuation thereby, a portable unit for supplying fluid under pressure to said motors, including a flow dividing valve, said valve having portions for actuated, a tracer unit adapted to -be detachably mounted on the machine with its tracer in cooperative 'relation with a pattern, and pressural control connections coupling the tracer unit for governing the position of said flow dividing valve.

27. A portable attachment forrendering machine tools having a pair of angularly related lead screws for effecting relative movement between work support and tool support adaptable for performance of contouring operations, comprising a portable unit having self-contained means for supplying fluid under pressure, apair of rotary hydraulic motors detachably connectible to said lead screws, a first control valve having means' for determining uni-directional actuation of one of said motors and reversible actuation ofthe other motor, a tracer head adapted to be detachably mounted upon the machine in cooperativerelation to a pattern carried by one of said supports, hydraulic means controlled by the tracer for governing the position of said control valve, an additional control valve interposed between the motors and their control valve for stopping and starting their actuation, said additional valve having a third position for reversibly connecting vsaid motors to the respective portions of the first named control valve..

28. A portable attachment for rendering' machine tools having a pair of angularly related lead screws for effecting relative movement between work support and tool support adaptable for per- .hydraulic motors detachably connectible to said, v

lead screws,v a iirst control valve having means for determining uni-directional actuation of one work support and a t001 Spindle Supported foknof said motors and reversible actuation of the rotation about an axis parallel to the direction of movement of said support, the combination with angularly related lead screws for effecting two- .l fdirectional movement of said support, including a rotary hydraulic feed motor, a rotary hydraulic profiling motor, means on said motors for detachable connection to the respective lead direction therefrom, whereby patterns 'in intaglio maybe produced in relief or vice versa, and retween the motors and their control valve for 29. In a tracer controlled circuit, the combination of a secondary valve, pressural control means for shifting the secondary valve, a tracer controlled valve, a manual controlled` valve means to selectively couple either of the last two-'named valves for varying the pressure of said pre'ssural n control means to govern the position of the secondary valve. Y

30. The combination with an operating circuit for governing variable actuation of a hydraulic motor including a control valve, ot a tracer controlled valve, a manual controlled valve, and

means to selectively couple either of the last twonamed valves for governing hydraulic actuation of said control valve.

31. In a machine tool having work and cutter supports, the combination of hydraulic actuating means detachably connectible for causing relative movement between said supports, a source of pressure iluid supply and a tracer head detachably connectible to the machine and having a verning said power'control unit in accordance with variations in a pattern for causing relative movements 1between said supports along a. path corresponding to the outline of the pattern.

LEIGH W. WRIGHT. y l

tracer engageable with a pattern for governing the supply of fluid pressure to saidl hydraulic actuating means in accordance with variations -in a pattern. 

